


Assumptions

by CottonCandyWhump



Series: Don’t Use Mint [2]
Category: Chicago Fire
Genre: Allergic reaction, Allergy fic, Anaphylaxis, Angst, Angst ish, Panic Attacks, Vomiting, Whump, anaphylactic shock, concussion, kelly being a bit of an ass, mint allergy, transfer
Language: English
Status: Completed
Published: 2019-06-23
Updated: 2019-06-28
Packaged: 2020-05-18 11:22:25
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 6
Words: 3,072
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/19333537
Author URL: https://archiveofourown.org/users/CottonCandyWhump/pseuds/CottonCandyWhump
Summary: Matt has an allergic reaction and Kelly’s assumptions land him in the hospital. What will happen when Matt realizes he can’t trust his team anymore?





	1. Chapter 1

“What the hell?!?” Kelly shouts when he walks into Matt’s office to see his best friend about to inject himself with something.

“Kelly, I swear it’s not what it looks like. I’ll explain in a minute,” Casey tells him, taking the cap off the syringe. Severide grabs the syringe out of his hand and holds it away from the other lieutenant.

“You’re doing drugs?!? What the hell Casey! Is this why you got Andy killed?!? You were high?!?” Severide shouts, quickly attracting the rest of the station.

“Sev, please! I need that back!” Casey says, already feeling his throat closing up.

“So you can get high and get the rest of us killed?!? I don’t think so!” Kelly yells, waving the syringe around. Casey looks behind Severide and sees his crew looking at him with a mix of disbelief, anger and betrayal.

“I’m not doing drugs! Just give it back! I’ll explain when I’m done!” Casey yells reaching for the syringe. He can feel his body starting to burn and he knows the hives are coming soon. It’s already hard to breathe, let alone carry on a conversation.

“Bullshit! If you’re not doing drugs then what the hell is this?!?” Severide asks, stepping back when Casey reaches for it again.

“Answer the question, Lieutenant,” Hermann snaps, stepping forward with his arms crossed.

“It’s my epipen and I need it right now!” Casey chokes out before his throat closes up and he passes out, falling to the ground. Kelly reads the label on the syringe and finds out that it is in fact an epipen.

“Oh shit,” Severide mutters as he quickly takes the epipen and jabs it into Casey’s thigh.

“Somebody get Shay and Dawson!” Herrmann shouts, kneeling beside the two lieutenants. Cruz runs off and returns a few seconds later with the chief and the two paramedics in tow.

“Mills, there’s an epipen in the top drawer of my desk,” Chief Boden says and the candidate runs off only to return a few seconds later, epipen in hand. The chief takes it and jabs it into the firefighters thigh, next to the other one.

“Dawson! Shay! Get the stretcher over here!”

~~~

Casey wakes up in the hospital a bit later and groans when he tries to move.

“You’re awake!” Severide says, smiling at him. Casey turns to look at him and is immediately reminded of why he was in the hospital.

“Get out.”

“What?” Kelly asks, his smile faltering.

“Out!” Casey snaps, the memory of the other lieutenants accusations too fresh in his mind. Severide glares at him and storms out of the room, slamming the door behind him.


	2. Chapter 2

A few minutes after Severide leaves, Hermann and the rest of the crew come in.

“What do you want?” Casey snaps, still pissed.

“You don’t need to be like that, Lieutenant,” Herrmann says, frowning.

“Just get out,” Casey says, massaging his temple. He’s too exhausted to deal with this right now.

“No. You’re being all annoyed for some reason. What did we do?” Herrmann asks, glaring.

“What did you?!? The reason I am lying in a hospital bed after nearly dying is because Severide started making accusations and all of you believed him without any proof or even a second thought! If you even had an ounce of trust in me, if one of you had spoken up and said ‘Hey, Severide. Maybe we should trust him! He’ll explain after!’ I wouldn’t be lying here right now! None of you said anything and I nearly died because none of you had any trust in me! And do you know what the worst part is? You thought I would be getting high and risking all your lives. You thought I would put your life in danger for a high. It’s obvious none of you trust me and at the moment I don’t think I can trust any of you! Now get out and send Boden in,” Casey tells them, watching as they stare in shock. 

Herrmann seems to realize he messed up and puts a hand on the lieutenants shoulder.

“Casey-,” he starts before Casey shoves his hand away.

“It’s lieutenant.” 

The crew leaves, realizing that they can’t change anything. Mills lingers after the others leave and turns to Casey.

“I’m really sorry for not speaking up, lieutenant. Are there any other allergies I should know about?” Mills asks. 

“Just me. Mint and penicillin,” Casey tells him and Mills nods, leaving the room.

Boden comes in a few seconds after.

“Mills said you needed to talm to me, Lieutenant?” Boden says, taking a seat beside the hospital bed.

“I would lie to put in for a transfer,” Casey tells him. Bodens eyebrows raise in surprise but to his credit, he doesn’t say anyting.

“When would you like to tell the station?” 

“They can find out on their own,” Casey says bitterly.


	3. Chapter 3

Casey returns to work a couple days later and immediately heads to his office, only leaving when they get a call. He doesn’t come out for lunch, refusing the food Mills brings him even after he insists it’s mint free. 

Boden goes in a couple times to sort out the transfer and inform him that there’s a space available as truck lieutenant in station 44. Casey accepts.

~~~

The next three days are spent the same way. Casey locking himself in his office, refusing lunch and only coming out for calls. On the fourth day, there’s no sign of Casey and his office is completely empty, as is his locker.

It’s at noon when Boden calls them all into the briefing room.

“Everyone, this is Lieutenant Sam Nanette. He will be in charge of truck from now on,” Boden tells the crew.

“Where’s Casey?” Severide asks, frowning.

“That’s not your concern,” Boden says.

~~~

“Can I ask what happened to the last lieutenant, sir?” Nanette asks as the chief shows him around.

“Lieutenant Casey had an allergic reaction and went to inject himself with his epipen. The crew thought he was on drugs and took it, refusing to give it back to him. He was rushed to the hospital and put in a transfer the same day,” Boden tells him. Nanette frowns but doesn’t say anything.

~~~

“Crew, this is Lieutenant Matthew Casey. He will be in charge of truck. I know it will be hard to move on from Alex but do your best to respect Lieutenant Casey and make him feel welcome,” the chief says, introducing Matt to the crew.

“Nice to meet you, lieutenant. Max Whyte,” a blond man introduces himself, shaking Matt’s hand. “This is Andrew Duvall, Ryan Kelly, Taylor Key, Jesse Cornwall and Andy Bennett.” 

“Nice to meet you all,” Matt says with a nod. He mostly gets nods and smiles back but the Ryan guy just glares at him. He would have to remember to keep an eye on him.

“Battalion 28, Truck 44, Engine 78. Ambulance 58. House fire.”

The firefighters suit up and are on the truck in seconds. In a minute, they’re driving down the street, lighs flashing and sirens blaring. They get to the scene seconds before another truck, putting them in charge.

“Duvall, Key, vent the roof. Cornwall, Kel- Ryan, you take the first floor. Bennett, Whyte with me, we’re on the second floor,” Casey orders, not quite able to say Severide’s name.

“Hey, Lieutenant! What do you want us to do?” The lieutenant from the other house asks. 

“Take some of your men into the basement and garage. We have a kid and a mom unaccounted for,” Casey orders. The other man nods and turns to his team.

“Mills, Herrmann, Otis, take the basement.”

“Otis is on hose,” Casey blurts before he can stop himself. The other lieutenant gives him a weird look but changes the order. Casey immediately heads back to his new team, ignoring the looks from the new 81 Lieutenant.

“Bennett! Whyte! We’re heading in!” Casey shouts as he puts his mask on. The other firefighters follow him into the burning building, the heat making them sweat. Casey presses on, finding the stairs and heading up, pausing when he hears something.

“Fire department! Call out!” Casey calls and gets a high pitched scream in return. 

He looks around, a flash of pink catching his eye. He wraps his arms around the blond girl just as the ceiling collapses, a flaming beam heading towards Bennett. 

Without a second thought, Casey shoves the girl into Whyte’s arms and runs forwards, shoving the other firefighter out of the way. The beam lands on Casey’s head, knocking him out.


	4. Chapter 4

He comes to about thirty seconds later and hears Bennett and Whyte shouting at him. 

“Lieutenant! You have to wake up, man!” Whyte shouts, tapping his face. Matt opens his eyes and finds himself looking up to see the worried faces of Whyte and Bennett.

“The girl,” Casey says, trying to push himself up only to realize that he's trapped under the same beam that knocked him out.

“We sent her out with some guys from 51,” Whyte says.

“We need to lift this thing off you,” Bennett tells him. The building gives another shudder, causing more debris to fall. Whyte quickly covers Casey’s unprotected head, his helmet having been crushed by the beam.

“The building isn’t safe. Get out of here,” Casey orders, coughing from all the dust.

“Sorry Lieutenant, not gonna happen. I don’t know about anyone else but I don’t want to be known as the house that got their lieutenant killed on his first day,” Whyte jokes as he and Bennett try lifting the beam off their lieutenant. Casey lets out a scream as they move the beam. Together, Whyte and Bennett manage to pull Casey out from underneath the beam.

“You alright, Lieutenant?” Bennett asks as he and Whyte loop one of Casey’s arms around their neck, each taking half his weight.

“Yeah. I’m good,” Casey mutters, his head lolling on his shoulders.

“Hey! You need to stay awake, Lieutenant,” Whyte says, giving him a little shake. 

“I’m good, I’m awake,” Casey says, opening his eyes.

“That’s great, Lieutenant. We’re almost there,” Whyte tells him, already able to see the door.

As soon as they make is outside, Casey is grabbed and shoved up against the wall, his head smacking against the brick.

“I can’t believe you! You ran away and couldn’t even tell us you put in a transfer?!? Are you that much of a coward, Casey?!?” Severide shouts, slamming the shorter lieutenant against the wall.

“Woah!” Bennett shouts at the same time Whyte yells “Hey!”

The two rush over to try and get the other firefighter off of their injured lieutenant.

“It’s none of your business what I do, Sev! You guys nearly killed me!” Casey yells back, trying to get Severide off of him. Severide backhands him and Casey’s head snaps to the side.

“Severide!” 

Kelly turns his head to see Boden walking over, obviously pissed off.

“What do you think you’re doing?!?” He yells, pulling him off of Casey.

While Boden’s yelling at Severide, Whyte and Bennett haul Casey to his feet and help him over to the ambulance, Casey stumbling between the two. They sit him up on the gurney and two of the paramedics head over.

“We haven’t even met and you’re already hurt. Hell of a first day,” one of them, his nametag reading N. Hegland, says. 

Matt just nods, not trusting himself to open his mouth. His stomach was turning and he was sure that if he responded verbally, the poor paramedic would be wearing last nights casserole. 

“So. Whyte said we’re looking at a possible head injury. Anything else, Lieutenant?” Hegland asks.

Casey shakes his head again, refusing to open his mouth. The paramedic looks up with a frown.

“I’m going to shine this light in your eyes real quick. That ok, Lieutenant?” 

Matt nods again and the other paramedic sighs.

“Say something! Please! You are literally killing me!” Hegland exclaims dramatically.

Matt shakes his head again, not wanting to throw up in front of his new team on the first day. He can feel his stomach contents making their way up his throat against his will and he slaps a hand over his mouth as he gags. 

“Shit. Whyte! Grab me one of the barf bags!” The paramedic calls as Casey heaves, vomiting down the paramedics uniform.

“There is no way in hell I am coming over there!” Whyte yells back. Casey looks up briefly to see he’s standing about forty feet away. 

“Somebody grab one of those goddamn bags now!” Hegland shouts, stepping out of Casey’s line of fire and looking down at his uniform. 

“Got it Heg!” Bennett calls and reaches into the ambulance, returning with one of the sick bags. He hands it to Hegland and the paramedic thrusts it under Casey’s chin just in time to catch the next wave. Hegland awkwardly pats the lieutenants back as Casey throws up. 

“Young! Get your ass in the driver's seat!” Hegland shouts and a brunette woman jumps into the driver's seat as Bennett helps Hegland gets Casey inside the ambulance.


	5. Chapter 5

“Possible concussion. He got hit in the head with a beam and had his head smacked against a brick wall. He vomited once,” Hegland says, motioning to his own uniform. The doctors take Casey into one of the rooms as they check him over and Hegland and Young take a seat in the waiting room.

~~~

“Hey,” Casey says, startling the two paramedics “Doc says it’s a moderate concussion. Should be fine.”

“That’s great. I’m not sure we’ve been introduced. I’m Justin Hegland. Heg. That’s Jessica Young, Jess,” Heg introduces himself, holding out a hand. Casey takes it, shaking it firmly.

“Casey. Sorry about,” Casey says, gesturing to Heg’s uniform. 

“I’m a paramedic. Trust me when I say it’s not the worst thing that’s happened to me,” Heg says with a grin.

The three head back to the station and relay the doctors words.

“Damn, Lieutenant. First day and you’ve already been to the hospital,” Key laughs, slapping him on the back.

Casey grins and looks around, seeing Whyte at the table by himself. Casey heads over, intending to thank him but as soon as Whyte sees him, he grabs his book and bolts. Casey frowns, wondering what he could have to make Whyte react like that. Not able to come up with anything, he just shakes his head and heads to his office to finish some paperwork from the call.

~~~

“Anyone know why he transferred?” Duvall asks over a game of poker.

“I heard his girlfriend slept with the other lieutenant,” Key says.

“Really? My cousin has a friend who works at 51. He said the lieutenants were fucking and the chief found out about it,” Cornwall tells him.

“You guys gossip like old ladies,” Whyte says, taking a seat as Key deals him in.

“How kind of you to grace us with your presence, My Lord,” Heg teases, bowing dramatically.

“Shut up, Heg.”

“Either way, you’re both wrong. His crew tried to kill him,” Heg says. 

“No way! If they tried to kill him, don’t you think they would have been arrested?” Young asks, rolling her eyes.

“He’s not that far off, actually,” somebody says. The firefighters whip around to see Casey standing there. Whyte immediately jumps up and leaves, leaving his jacket behind. 

“What’s his deal?” Casey asks, nodding at the door Whyte left out of.

“He has a thing about vomit,” Key says, putting quotation marks around thing. “Check this out.”

Key heads over to the fridge and gets a glass of warm water before heading out the door Whyte left, motioning for Matt to follow. Curious, Casey heads out behind him. They creep up behind Whyte who’s reading something or other and Key makes a gagging noise before splashing the water against the back of Whytes neck. The reaction is immediate. Whyte pales, his skin practically white and bolts out of the room with a strangled sob.

Key doubles over laughing and Matt hears the guys in the other room laughing. Casey just frowns and heads towards the locker room where the other man fled. He finds Max in the shower fully clothed under boiling water mid panic attack. 

“Hey. There’s nothing on you. It was just water,” Matt says, putting a hand on Max’s arm.

“I’m going to turn the water off now, okay?” Casey tells him before turning the water off and draping a towel over the man's shoulders. He can hear Whyte struggling to control his breathing and Matt grabs his hand, putting it on his chest.

“You’re having a panic attack, Max. Deep breathes,” Casey says and slowly but surely he can feel Max matching his breathes to Matt’s. Once his breathing has calmed down, Max looks around and realizes what’s going on.

“Lieutenant! I’m so sorry! I wasn’t-,” Whyte starts before Casey cuts him off.

“Hey. It’s fine. We all have our kryptonite. I can’t stand elevators,” Casey tells him. Max nods and the two change into dry clothes before heading out.


	6. Chapter 6

It’s been three months since Casey transferred and he hadn’t seen anyone from 51 since the house fire. That’s probably why he was surprised when Whyte came to tell him he had a visitor. As he heads outside the station to see who it was, he couldn’t help speculating. Maybe something it was Herrmann needing a hand with a construction job. Or Boden with something for him to sign. 

He definitely wasn’t expecting Severide to be standing outside the station sheepishly, the squad truck parked outside. As soon as Matt sees him, he turns to head back inside.

“Matt wait,” Kelly says, his voice desperate.

“What do you want?” Casey snaps, not wanting to deal with this again. 

“Can we talk?”

Casey thinks about it for a second. He can see the other firefighters nearby, ready to step in if it goes south. He motions for Whyte to come over and nods to Severide.

“Make it quick.”

“I know I’ve been a really shitty friend and I’m really sorry about it. Please come back to 51. It’s not the same without you,” Kelly pleads.

Matt’s face softens and he sighs.

“I’ve found something here, Sev. This is my house now. I’m not coming back.”

“I get it. Just know that there’s a spot at 51 if you change your mind.”

Casey nods. 

“I’ll keep that in mind.”


End file.
